package irsystem.model;
//<editor-fold state="collapsed" desc="description">
/*

   Porter stemmer in Java. The original paper is in

       Porter, 1980, An algorithm for suffix stripping, Program, Vol. 14,
       no. 3, pp 130-137,

   See also http://www.tartarus.org/~martin/PorterStemmer

   History:

   Release 1

   Bug 1 (reported by Gonzalo Parra 16/10/99) fixed as marked below.
   The words 'aed', 'eed', 'oed' leave k at 'a' for step 3, and b[k-1]
   is then out outside the bounds of b.

   Release 2

   Similarly,

   Bug 2 (reported by Steve Dyrdahl 22/2/00) fixed as marked below.
   'ion' by itself leaves j = -1 in the test for 'ion' in step 5, and
   b[j] is then outside the bounds of b.

   Release 3

   Considerably revised 4/9/00 in the light of many helpful suggestions
   from Brian Goetz of Quiotix Corporation (brian@quiotix.com).

   Release 4

*/
//</editor-fold>

import java.io.*;

/**
  * Stemmer, implementing the Porter Stemming Algorithm
  *
  * The Stemmer class transforms a word into its root form.  The input
  * word can be provided a character at time (by calling add()), or at once
  * by calling one of the various stem(something) methods.
  */

public class Stemmer {

    /* atribut-atribut yang dimiliki oleh kelas Stemmer */
        private char[] b;
        private int i,                          /* offset into b */
                   i_end,                       /* offset to end of stemmed word */
                   j, k;
        private static final int INC = 50;      /* unit of size whereby b is increased */

    /* constructor - default constructor */
        public Stemmer()
        {  b = new char[INC];
          i = 0;
          i_end = 0;
        }

    /* getter */
        /**
        * Returns the length of the word resulting from the stemming process.
        */
            public int getResultLength() { return i_end; }

        /**
        * Returns a reference to a character buffer containing the results of
        * the stemming process.  You also need to consult getResultLength()
        * to determine the length of the result.
        */
            public char[] getResultBuffer() { return b; }

    /* method-method yang dimiliki oleh kelas Stemmer */
        /**
        * Add a character to the word being stemmed.  When you are finished
        * adding characters, you can call stem(void) to stem the word.
        */
            public void add(char ch) {
                if (i == b.length) {
                    char[] new_b = new char[i+INC];
                    for (int c = 0; c < i; c++) new_b[c] = b[c];
                    b = new_b;
                }
                b[i++] = ch;
            }


        /** Adds wLen characters to the word being stemmed contained in a portion
        * of a char[] array. This is like repeated calls of add(char ch), but
        * faster.
        */
            public void add(char[] w, int wLen) {
                if (i+wLen >= b.length) {
                    char[] new_b = new char[i+wLen+INC];
                    for (int c = 0; c < i; c++) new_b[c] = b[c];
                    b = new_b;
                }
                for (int c = 0; c < wLen; c++) b[i++] = w[c];
            }

        /**
        * After a word has been stemmed, it can be retrieved by toString(),
        * or a reference to the internal buffer can be retrieved by getResultBuffer
        * and getResultLength (which is generally more efficient.)
        */
            public String toString() { return new String(b,0,i_end); }

        /* cons(i) is true <=> b[i] is a consonant. */
            private final boolean cons(int i) {
                switch (b[i]) {
                    case 'a':
                    case 'e':
                    case 'i':
                    case 'o':
                    case 'u':
                        return false;
                    case 'y':
                        return (i==0) ? true : !cons(i-1);
                    default:
                        return true;
                }
            }

        /* m() measures the number of consonant sequences between 0 and j. if c is
          a consonant sequence and v a vowel sequence, and <..> indicates arbitrary
          presence,

             <c><v>       gives 0
             <c>vc<v>     gives 1
             <c>vcvc<v>   gives 2
             <c>vcvcvc<v> gives 3
             ....
        */
            private final int m() {
                int n = 0;
                int i = 0;
                while(true) {
                    if (i > j) return n;
                    if (! cons(i)) break; i++;
                }
                i++;
                while(true) {
                    while(true) {
                        if (i > j) return n;
                        if (cons(i)) break;
                        i++;
                    }
                    i++;
                    n++;
                    while(true) {
                        if (i > j) return n;
                        if (! cons(i)) break;
                        i++;
                    }
                    i++;
                }
            }

        /* vowelinstem() is true <=> 0,...j contains a vowel */
            private final boolean vowelinstem() {
                int i; for (i = 0; i <= j; i++) if (! cons(i)) return true;
                return false;
            }

        /* doublec(j) is true <=> j,(j-1) contain a double consonant. */
            private final boolean doublec(int j) {
                if (j < 1) return false;
                if (b[j] != b[j-1]) return false;
                return cons(j);
            }

        /* cvc(i) is true <=> i-2,i-1,i has the form consonant - vowel - consonant
          and also if the second c is not w,x or y. this is used when trying to
          restore an e at the end of a short word. e.g.

             cav(e), lov(e), hop(e), crim(e), but
             snow, box, tray.

        */
            private final boolean cvc(int i) {
                if (i < 2 || !cons(i) || cons(i-1) || !cons(i-2)) return false; {
                    int ch = b[i];
                    if (ch == 'w' || ch == 'x' || ch == 'y') return false;
                }
                return true;
            }

            private final boolean ends(String s) {
                int l = s.length();
                int o = k-l+1;
                if (o < 0) return false;
                for (int i = 0; i < l; i++) if (b[o+i] != s.charAt(i)) return false;
                j = k-l;
                return true;
            }

        /* setto(s) sets (j+1),...k to the characters in the string s, readjusting
          k. */
            private final void setto(String s) {
                int l = s.length();
                int o = j+1;
                for (int i = 0; i < l; i++) b[o+i] = s.charAt(i);
                k = j+l;
            }

        /* r(s) is used further down. */
            private final void r(String s) { if (m() > 0) setto(s); }

        /* step1() gets rid of plurals and -ed or -ing. e.g.

              caresses  ->  caress
              ponies    ->  poni
              ties      ->  ti
              caress    ->  caress
              cats      ->  cat

              feed      ->  feed
              agreed    ->  agree
              disabled  ->  disable

              matting   ->  mat
              mating    ->  mate
              meeting   ->  meet
              milling   ->  mill
              messing   ->  mess

              meetings  ->  meet

        */
            private final void step1() {
                if (b[k] == 's') {
                    if (ends("sses")) k -= 2; else
                    if (ends("ies")) setto("i"); else
                    if (b[k-1] != 's') k--;
                }
                if (ends("eed")) { if (m() > 0) k--; } else
                if ((ends("ed") || ends("ing")) && vowelinstem()) {
                    k = j;
                    if (ends("at")) setto("ate"); else
                    if (ends("bl")) setto("ble"); else
                    if (ends("iz")) setto("ize"); else
                    if (doublec(k)) {
                        k--;
                        {  int ch = b[k];
                           if (ch == 'l' || ch == 's' || ch == 'z') k++;
                        }
                    }
                    else if (m() == 1 && cvc(k)) setto("e");
                }
            }

        /* step2() turns terminal y to i when there is another vowel in the stem. */
            private final void step2() { if (ends("y") && vowelinstem()) b[k] = 'i'; }

        /* step3() maps double suffices to single ones. so -ization ( = -ize plus
          -ation) maps to -ize etc. note that the string before the suffix must give
          m() > 0. */
            private final void step3() {
                if (k == 0) return; /* For Bug 1 */
                    switch (b[k-1]) {
                        case 'a':
                            if (ends("ational")) { r("ate"); break; }
                            if (ends("tional")) { r("tion"); break; }
                            break;
                            case 'c': if (ends("enci")) { r("ence"); break; }
                                     if (ends("anci")) { r("ance"); break; }
                                     break;
                            case 'e': if (ends("izer")) { r("ize"); break; }
                                    break;
                            case 'l': if (ends("bli")) { r("ble"); break; }
                                     if (ends("alli")) { r("al"); break; }
                                     if (ends("entli")) { r("ent"); break; }
                                     if (ends("eli")) { r("e"); break; }
                                     if (ends("ousli")) { r("ous"); break; }
                                     break;
                            case 'o': if (ends("ization")) { r("ize"); break; }
                                     if (ends("ation")) { r("ate"); break; }
                                     if (ends("ator")) { r("ate"); break; }
                                     break;
                            case 's': if (ends("alism")) { r("al"); break; }
                                     if (ends("iveness")) { r("ive"); break; }
                                     if (ends("fulness")) { r("ful"); break; }
                                     if (ends("ousness")) { r("ous"); break; }
                                     break;
                            case 't': if (ends("aliti")) { r("al"); break; }
                                     if (ends("iviti")) { r("ive"); break; }
                                     if (ends("biliti")) { r("ble"); break; }
                                     break;
                            case 'g': if (ends("logi")) { r("log"); break; }
                    }
            }

        /* step4() deals with -ic-, -full, -ness etc. similar strategy to step3. */
            private final void step4() {
                switch (b[k]) {
                    case 'e':
                        if (ends("icate")) { r("ic"); break; }
                        if (ends("ative")) { r(""); break; }
                        if (ends("alize")) { r("al"); break; }
                        break;
                    case 'i':
                        if (ends("iciti")) { r("ic"); break; }
                        break;
                    case 'l':
                        if (ends("ical")) { r("ic"); break; }
                        if (ends("ful")) { r(""); break; }
                        break;
                    case 's': if (ends("ness")) { r(""); break; }
                        break;
                }
            }

        /* step5() takes off -ant, -ence etc., in context <c>vcvc<v>. */
            private final void step5() {
                if (k == 0) return; /* for Bug 1 */
                    switch (b[k-1]) {
                        case 'a':
                            if (ends("al")) break; return;
                        case 'c':
                            if (ends("ance")) break;
                            if (ends("ence")) break; return;
                        case 'e':
                            if (ends("er")) break; return;
                        case 'i':
                            if (ends("ic")) break; return;
                        case 'l':
                            if (ends("able")) break;
                            if (ends("ible")) break; return;
                        case 'n':
                            if (ends("ant")) break;
                            if (ends("ement")) break;
                            if (ends("ment")) break;
                            /* element etc. not stripped before the m */
                            if (ends("ent")) break; return;
                        case 'o':
                            if (ends("ion") && j >= 0 && (b[j] == 's' || b[j] == 't')) break;
                                            /* j >= 0 fixes Bug 2 */
                            if (ends("ou")) break; return;
                            /* takes care of -ous */
                        case 's':
                            if (ends("ism")) break; return;
                        case 't':
                            if (ends("ate")) break;
                            if (ends("iti")) break; return;
                        case 'u':
                            if (ends("ous")) break; return;
                        case 'v':
                            if (ends("ive")) break; return;
                        case 'z':
                            if (ends("ize")) break; return;
                        default:
                            return;
                    }
                if (m() > 1) k = j;
            }

        /* step6() removes a final -e if m() > 1. */
            private final void step6() {
                j = k;
                if (b[k] == 'e') {
                    int a = m();
                    if (a > 1 || a == 1 && !cvc(k-1)) k--;
                }
                if (b[k] == 'l' && doublec(k) && m() > 1) k--;
            }

        /** Stem the word placed into the Stemmer buffer through calls to add().
        * Returns true if the stemming process resulted in a word different
        * from the input.  You can retrieve the result with
        * getResultLength()/getResultBuffer() or toString().
        */
            public void stem() {
                k = i - 1;
                if (k > 1) { step1(); step2(); step3(); step4(); step5(); step6(); }
                i_end = k+1; i = 0;
            }

        /** Test program for demonstrating the Stemmer.  It reads text from a
        * a list of files, stems each word, and writes the result to standard
        * output. Note that the word stemmed is expected to be in lower case:
        * forcing lower case must be done outside the Stemmer class.
        * Usage: Stemmer file-name file-name ...
        */
//            public static void main(String[] args) {
//                char[] w = new char[501];
//                Stemmer s = new Stemmer();
//                try {
//                    FileInputStream in = new FileInputStream("data/test/cisi.all");
//
//                    try {
//                        while(true) {
//                            int ch = in.read();
//                            if (Character.isLetter((char) ch)) {
//                                int j = 0;
//                                while(true) {
//                                    ch = Character.toLowerCase((char) ch);
//                                    w[j] = (char) ch;
//                                    if (j < 500) j++;
//                                    ch = in.read();
//                                    if (!Character.isLetter((char) ch)) {
//                                        /* to test add(char ch) */
//                                        for (int c = 0; c < j; c++) s.add(w[c]);
//
//                                        /* or, to test add(char[] w, int j) */
//                                        /* s.add(w, j); */
//
//                                        s.stem();
//                                        {  String u;
//
//                                        /* and now, to test toString() : */
//                                        u = s.toString();
//
//                                        /* to test getResultBuffer(), getResultLength() : */
//                                        /* u = new String(s.getResultBuffer(), 0, s.getResultLength()); */
//
//                                        System.out.print(u);
//                                        }
//                                        break;
//                                    }
//                                }
//                            }
//                            if (ch < 0) break;
//                            System.out.print((char)ch);
//                        }
//                    } catch (IOException e) {
//                        System.out.println("error reading " + "data/test/cisi.all");
//                    }
//                } catch (FileNotFoundException e) {
//                    System.out.println("file " + "data/test/cisi.all" + " not found");
//                }
//            }
}